This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. To identify plant cell wall factors limiting digestibility and forage utilization in sustainable dairy farming, we will 1. Characterize plants with genetically modified lignin-pathways in order to develop novel approaches for improving forage utilization and provide insight into the effects of lignin composition on cell wall digestability and formation of indigestible residues. 2. Determine the intrinsic chemical characteristics of indigestible residues in order to elucidate mechanisms that limit their digestion by dairy cows and reduce their negative impact.